Rack is a modular Ruby web server interface. Prior to 2.2.25, 3.1.23, and 3.2.8, Rack::Multipart::Parser can retain parsed data in its internal StringScanner buffer when reads end inside or immediately after multipart headers. An unauthenticated attacker can align many small parts with rack.multipart.buffer_size boundaries so the buffer grows with the request despite per-field, header, and preamble limits, causing a worker to exhaust memory. The attack requires only a well-formed multipart body and affects applications that parse multipart requests. This issue is fixed in versions 2.2.25, 3.1.23, and 3.2.8.
Metrics
Affected Vendors & Products
Advisories
No advisories yet.
Fixes
Solution
No solution given by the vendor.
Workaround
No workaround given by the vendor.
References
History
Tue, 10 Nov 2026 00:15:00 +0000
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Rack
Rack rack |
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| Vendors & Products |
Rack
Rack rack |
Mon, 09 Nov 2026 22:15:00 +0000
| Type | Values Removed | Values Added |
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| Description | Rack is a modular Ruby web server interface. Prior to 2.2.25, 3.1.23, and 3.2.8, Rack::Multipart::Parser can retain parsed data in its internal StringScanner buffer when reads end inside or immediately after multipart headers. An unauthenticated attacker can align many small parts with rack.multipart.buffer_size boundaries so the buffer grows with the request despite per-field, header, and preamble limits, causing a worker to exhaust memory. The attack requires only a well-formed multipart body and affects applications that parse multipart requests. This issue is fixed in versions 2.2.25, 3.1.23, and 3.2.8. | |
| Title | Rack: Multipart parsing allows DoS via unbounded scan buffer growth | |
| Weaknesses | CWE-400 | |
| References |
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| Metrics |
cvssV3_1
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Projects
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Status: PUBLISHED
Assigner: GitHub_M
Published:
Updated: 2026-11-09T22:02:38.334Z
Reserved: 2026-11-09T17:45:35.936Z
Link: CVE-2026-125111
No data.
Status : Received
Published: 2026-11-09T22:18:42.433
Modified: 2026-11-09T22:18:42.433
Link: CVE-2026-125111
No data.
OpenCVE Enrichment
Updated: 2026-11-10T00:00:11Z
Weaknesses